title: Heparinized blood better preserves cellular energy charge and vascular functions of intraoperatively stored saphenous vein grafts in comparison to isotonic sodium-chloride-solution.
abstract: OBJECTIVE
  Several studies have addressed the optimal storage conditions for vascular grafts during surgery. The results remain contradictionary. This may be attributed to the fact, that the various vascular beds have a different sensitivity to storage. We analyzed the impact of storage in isotonic saline solution (NaCl) or heparinized blood the vascular functions of human saphenous vein grafts. Special care was taken to choose storage conditions which are relevant for intraoperative storage of a saphenous vein graft in a setting of coronary artery bypass grafting with vein and internal mammary artery as grafts.
  
  
  METHODS
  Intraoperatively isolated V. saphena-segments (n = 36) were stored in NaCl or heparinized blood for approximately 30 minutes at room temperature. Subsequently, the segments were examined in a Mulvany-myograph. Following preconstriction with norepinephrine, concentration-relaxation curves were assessed for bradykinin and sodium-nitroprusside to assess developed vessel-wall tension as well as endothelium- and smooth-muscle-cell dependent vasorelaxation. The availability of adenosintriphosphate (energy charge) was determined based on liquid chromatography measurements of nucleotide tissue levels.
  
  
  RESULTS
  Mean storage time was 27.4 ± 2.4 min in NaCl- and 26.3 ± 2.7 min in blood-group, respectively. After this period, receptor-dependent and-independent maximum of developed vessel wall tension was significantly reduced in NaCl-group (p = 0.05 and p = 0.045, respectively). Furthermore, the energy charge was significantly (p = 0.046) better preserved after blood storage (74 ± 1%) in comparison to NaCl-group (68 ± 2%). Endothelium-induced vasodilatation in response to bradykinin reached only 12.3 ± 2.5% in NaCl-group, but 19.3 ± 5.2% in blood-group (p = 0.033). Alike, EC50-concentration of bradykinin for half-maximal relaxation was significantly lower in blood- than in NaCl-group (log EC50 -7.08 ± 0.3 and -5.91 ± 0.4; respectively; p = 0.046). Endothelium-independent smooth muscle relaxation in response to sodium-nitroprusside was not different between both groups.
  
  
  CONCLUSIONS
  Heparinized blood better preserves vascular contractile and endothelial functions of the saphenous vein graft. Storage in NaCl rapidly compromises vascular functions and impaires cellular energy. NaCl should no longer be recommended for intraoperative storage of harvested V. saphena grafts.
authors.affiliation: Department of Cardiac Surgery, University Heart Center Dresden, Dresden, Germany.
authors.forename: Manuel
authors.initials: M
authors.lastname: Wilbring
authors.affiliation: Institute for Physiology, Medical Faculty 'Carl Gustav Carus' Dresden, Dresden, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Ebner
authors.affiliation: Institute for Physiology, Medical Faculty 'Carl Gustav Carus' Dresden, Dresden, Germany.
authors.forename: Katrin
authors.initials: K
authors.lastname: Schoenemann
authors.affiliation: Department of Cardiac Surgery, University Heart Center Dresden, Dresden, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Knaut
authors.affiliation: Department of Cardiac Surgery, University Heart Center Dresden, Dresden, Germany.
authors.forename: Sems Malte
authors.initials: SM
authors.lastname: Tugtekin
authors.affiliation: Institute for Physiology, Medical Faculty 'Carl Gustav Carus' Dresden, Dresden, Germany.
authors.forename: Birgit
authors.initials: B
authors.lastname: Zatschler
authors.affiliation: Department of Cardiac Surgery, University Heart Center Dresden, Dresden, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Waldow
authors.affiliation: Department of Cardiac Surgery, University Heart Center Dresden, Dresden, Germany.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Alexiou
authors.affiliation: Department of Cardiac Surgery, University Heart Center Dresden, Dresden, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Matschke
authors.affiliation: Institute for Physiology, Medical Faculty 'Carl Gustav Carus' Dresden, Dresden, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Deussen
mesh_terms: D000368:Aged; D001026:Coronary Artery Bypass / Q000379:methods*; D005260:Female; D006493:Heparin; D006801:Humans; D008297:Male; D009926:Organ Preservation / Q000379:methods*; D019188:Organ Preservation Solutions; D012501:Saphenous Vein / Q000378:metabolism / Q000502:physiology* / Q000637:transplantation*; D012965:Sodium Chloride; D014665:Vasodilator Agents
chemical_list: D019188:Organ Preservation Solutions; D014665:Vasodilator Agents; D012965:Sodium Chloride; D006493:Heparin
keywords: CABG; blood; endothelial vascular function; preservation; saphenous vein graft; storage solution